It is extremely
likely that there will be a valve to piston 'interference' problem on decelleration. Because of the build geometry, Midget's 999cc jewel has no room to spare in the valve to piston clearance department. The reason for the added tensioner arrangement is the 'slack' in the cogs/chain. If there was no slack in the setup, no tensioner would be required. A belt style cam drive
might provide less 'slack', but this is an unknown at this time, not to mention the added expense. Once the cam is installed and the actual valve to piston clearance is verified, it is possible that a tensioner arrangement is not required. Until that time, however, better to plan for the worst case possible. That's better than a last minute 'fire drill', as we all have done at one time or another.
Also, the pivot bolt should be towards the crank cog, the
leading side of the chain motion, as you have correctly installed it.
Midget, have you thought about leaving the pivot bolt long, as in long enough to go through the cover? The extra support would be minimal, but in the event of the bolt breaking, a nylock jam nut on the cover would perhaps prevent the disaster of the bits being swallowed at 8000 rpm.........
The mockup engine I have has .43" clearance between the tin front cover & the back of the crankshaft damper. That should be enough for a 1/4" jam nut/washer. The hole in the cover would probably need to be sealed with some "schmoo" like high temp/regular RTV. It is impossible to tell if the crankshaft front seal is or is not in the way though. I'm thinking that the OD of the seal is about the same diameter as the OD of the crank cog, so perhaps there will be enough room to squeak all this into the space available.
Just a couple of small observations: 1) The proper tool makes any pita ("pain in the keister") job easier, and therefore, more likely to get accomplished. And, 2) You'll have plenty of time to sleep when you're dead!!

Fordboy
P.S. Will be in Texas Wednesday through Sunday. Need to co-ordinate on hoses/fittings; w/pump drive & clutch slave. Willing to do assembly/other work to prepare car (?) for dyno and Wendover.