2nd the Rev...probably the only one that will fit anyhow.
I'd recommend the Ali Sparco Pro mouns that go under the seat. You can do a trim job to get them round the rear chassis cross rail. They're the best quality fit and provide the lowest seating position.
Not strictly true- Mulfab do correctly fitting side mounting Morgan ones that fit the seat as low as possiblehttp://www.mulfab.co.uk/our-products/7/other-miscellaneous
If you are feeling really adventurous it is also possible to modify the crossmember behind the seats to gain legroom and lose another inch or so of seat heighthttp://www.demon-tweeks.co.uk/performanc...eat-mounts-pair
You'll also need to trim the seat edge round the transmission tunnel - just pull back the cover and trim with saw. If you are fitting 2 you'll need to trim the wing section where your shoulders go as the two seats foul each other when fitted.