Today I spent a couple of hours cleaning down a generally getting the engine bay ready to have the new engine fitted. This involved large quantities of solvent and whole roll of workshop paper and much cr4p under my fingernails. However the engine bay is now pretty clean and non slimey to the touch. Which will make working in there much easier and should also improve the quality of the impending welding.
You can clearly see the scars of previous development work on this chassis, the triangulation tubes have plainly been moved around to accept different engines from time to time and the floor bracing has been modified to accept different diff\ chain wheel combinations plus there are no end of areas where brackets have been welded on and subsequently ground off when not needed. In fact one of the major tubular cross members has been removed and replaced with a plate which will clearly flex I’ll be replacing this with a new tube in the hope of increasing chassis rigidity.
Incidentally the mounting ears you can see on the front chassis rails appear to be just wide enough apart that I could use them for the new side on mounts for the CBR, that could be handy.
Next job is to remove the driveshafts as these will also need changing to match the new diff, an then cut out the diagonal cruciform bracing at the far end of the chassis. 
The configuration of the new diff is to have the chain wheel behind the drive shafts (in the picture the engine mounts to the left), so a chunk of the casing needs to stick our right where there is a chassis rail. My plan is to replace the tubular bracing with a shear plate not unlike the one in the pictures of the new chassis, and I’ve found a local company (Lasercut in Peterborough) who will make me a one off economically. So this weekend some careful measuring and a couple of hours with a CAD package should see that sorted.
Once the cross bracing is cut out I can start fitting the new engine + diff proper.