Hiya,
Usually it's a case of matching the colour of the one that's in there. Are you going to do a coolant flush? If so, no worries about mixing colours, you can start fresh
Mine is an 87 305 TPI so likely it's the same engine as yours?
I use Comma G48 in mine, use the same in the 2nd Gen Camaro which has a 74-76 350 in it. It's available from Halfords / local motorist discount centre and online. I got the 5 litre concentrate via ebay for under £30. You can also get it as ready mix if you prefer. Here's a 2litre concentrate:
http://www.halfords.com/motoring/engine ... nt-conc-2l
I tend to steer clear of Halfords own brand oils and lubricants, just personal preference though, there's probably nothing bad about them.
Hope that helps!
Cheers,
Ray
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