Thanks for all the good inputs.

I broke the snout off of the first mini-starter, and actually suspected a misalignent. That's why I bought a second unit and I grinded the snout to avoid any tension building up when bolting the starter to the block. Now this 2:nd doesn't seem to have broken the snout off, it spins but it doesn't engage the gears anymore. I suspect the starter shaft may be slightly bent or similar. It anyway hasn't sounded healthy for the last few days so I guess it's ready for the thrash can.

I broke this second unit having the engine management set up for 3 crank revolutions before activating ignition. I will increase this to 6. Cranking ignition was set at -1 degree ATDC. What I also will do is to decrease the dwell time from 4 ms to 3 ms, to try to minimize any risk of premature firing in the coils.

My static compression is 12.4, which shouldn't be a problem.
I however have a mild cam allowing for the power brakes to work in town, and this means I have a fairly high cylinder pressure. The dynamic compression is approx 9.2

Thanks again, sounds like a Powermaster is the way to go?