Mick,
Cant help on diagnostic advice but I think the price is a bit high for a motor with that manyK's.
With 78k's on it it will probably need a freshen up in the ring dept and while you are at it you would need to change the big end and main bolts to ARP , add a double row timing chain and blue print the
oil pump.
Get a Textralia clutch and you have a pretty good set up especially in a Harrison......if I was doing it all again it would be a Harrison with an LS2
If you want more info on LS1/LS2 have a look at LS1.com.au
Phil
