I have finished building the exhaust system for my roadster, using a rolling chassis with motor fitted as a fitting mule. It has no firewall, so I was measuring up my 25 roadster to see how much trimming I might need to do.
The steering column is lowered and moved to the outside, so it clears that. Then the thought occurred to me that the rest of the fitting is the same as you LHD fellows have to cope with, so the question is does the metal firewall on a 25 T need any trimming to fit the manifold?
The manifold casting had the moulding seams rather roughly ground, so I re-finished those with an angle grinder to get rid of the irregularities and then used a well worn burr in my die grinder over the area to get rid of the grinding marks. If you hold the die grinder loosely and let it bounce a bit, the resulting finish is much like the heavy blasting finish on the original casting.
I'll await your collective wisdom before getting started on the fitting.
Allan from down under.