If you can get Tim Ayres or someone to look at the engine spec in advance of a visit , let us know what it says.
The Rover V8 (of that era) was designed to lug around a 2500 kilo 4x4 and produce a lot of low down torque , which is great for that purpose , but for a light sports car it doesn't really make for a free revving engine.
The John Eales mods generally use some intake and head modifications plus a better cam, better clutch and everything nicely balanced and lightened. I won't say it transforms the car , but you will notice an immediate difference . It revs much more quickly and cleanly, and will pull right up to 6000 rpm (but peak torque is somewhat lower of course) Many of your ex TVR colleagues will probably have had similar work done.
Also make sure that the electronics have had 2 chips , one for fuelling and one for electronics, not cheap but so worthwhile.