Yep. I'm with you there cooperman! Dedicated cutting wheel and don't push it in aluminium and nothing will get hot! nor will the wheel clog.
But if anyone is worrying about that part of the fit then really you probably haven't got the skill to undertake the job. Just in case though and for information if you are attempting it!
The first job after removing the old wing is to fit the new unpainted wing and when that is all correct remove and get it painted and ready for re-fitting permanently. Probably a good idea to use new beading as well as you need to rely on that as a water seal. In the past I have used a low modulus soft set silicone to the inside edge on top of the bead. It is just a micro bead and can be applied before you fully tighten the wing fastenings into the wooden arch. Basically fit the wing in place and leave all fixings loose so you can move the wing. When happy that you can hold the wing into the fully fixed position apply the micro bead. Take your time, low modulus silicone doesn't cure like the stuff that smells of vinegar! The bead should be on the flat top seal section of the bead where it joins the bulbous part that sits outside and on the wing, in size about 1/8". Now start tightening everything up slowly observing as you go the whole wing position. when just moveable and you are happy with the position, ie. its all touching in the right place hold the wing by slightly tightening the wing to running board fixing ,the wing stay and the rear most fixing. Now you can tighten the fastenings that hold the wing to the ply wood inner wheel arch. I start at the middle or uppermost fixing. As you do this you must make sure that the wing is rising without being forced up into place or deforming the alloy and also that you are holding the beading in the correct place. When you reach a point of tightness that just holds the bead secure stop and continue with the rest of the timber arch fixings by alternating left of centre then to the right of the centre fixing., continue until all are fitted paying attention to bead position as you go! This will position the wing without stressing anything. Now you can tighten the remaining fixings. DO NOT OVERTIGHTEN ANY OF THE FIXINGS ACCOSIATED WITH THE WING BEAD, It will distort the alloy of the wing and over compress the bead causing it to bulge out onto the wing in that area! Just tight enough to hold it firm and no more.
With a clean cloth wipe any silicone that may have squeezed out of the top of the bead, then finally with a creased fold remove as much of the excess form the top gap, you shouldn't be able to see any silicone evidence at all! When all is fitted and you are happy with the position I then remove the wheel arch to ply fixings one by one, starting with the top centre first. I inject a little squirt of the silicone into the hole and then refit the screw or nut etc. depending of Morgan's preferred method when your car was built. what ever the fixing method on your car there will always be a cavity created there which can hold water and if you look at the removed wing you will see the corrosive evidence of this around the fixing hole and as we know steel, alloy and water are ideal for causing galvanic corrosion. If you do that in a day then you are really doing well! Now go in and finish it tomorrow or another day!
Last tips: When you refit the lights change out those silly wire connectors MMC use for waterproof bullet connectors. Re apply the black wax body protection to the inner jointing areas to seal the alloy/wood joint. It is Dinitrol chassis black and you can buy a single aerosol spray can from Rejel on line. Lastly, use Three-in-one oil between the bottom of the bead and the alloy wing. This will protect the wing at the mounting surface from potential corrosion caused by water sitting there, erosion of the painted surface from the micro movement when the car is being driven and also squeaking noises from the same. Three-in-one is the recommended service lubricant oil by MMC although if I had leather covered beading I would probably opt for ACF-50
