Thanks for the input and advice guys, I will take it on board for sure. A couple of points:
Yes, will change filter as well as oil at 25 hours.
Purolator filter is actually a superior product to Rycu one.... costs more but made from better materials.
I'll know the mech pump is working because I'll turn the electric one off to check. It is advised to leave on to prevent vapour lock in hot weather by pushing fuel up rather than sucking it up. I know it makes no difference to TBO: just a point of interest.
There will be less carbon build-up in heads and around rings when using 98 octane mogas.
Brent, I agree with you, on reflection, regarding the frequency of tappet adjustments.
BigPete, the motor was turned over or started frequently (owned by a mechanic ) to keep it lubricated.
Once again, thanks.