I assume this is as a result of your fun rather than cracks.
You will get the 2014/16 hybrid chassis which has the newer bevel box mount built in. It will also have the side mounting for the regulator.
The stage1/2 upgrades are air filter and exhaust so there's not that much saving in fitting them with the new chassis, but if you've not done them already then you should.
Whilst you have the engine out - If you have the Centa compensator then replace the rollers (approx. £30 for 4) and check the clutch.
Consider beefing up the fuel tank mounts and definitely carry out the Walbro mod to the fuel pump
Take the opportunity to dynamat or similar at least the rear bulkhead and transmission tunnel.
Maybe change things such as the rear gearbox mount, rear wheel bearings.
Good luck!
