I have done this and there are no real problems. Disconnect everything from the carby - all the wiring & obviously throttle cable, fuel lines, egr pipe etc. You can get away with leaving the webber on the manifold & reomve the manifold.
Get a new gasket, use same bolts or get longer bolts if new manifold has increased flange thickness. Use loctite on all bolts and tighten to correct torque in correct sequence. Then put your carby on. Tighten 4 bolts evenly.
You will need to change the trottle cable, an XE V8 cable is long enough. You may also want to run a spacer bettween carb & manifold with an outlet for PCV hose to oil cap. Running a decent size are cleaner will be you biggest problem.