[Spenny_b]

Meant to say, wrt to Ti valve retainers, my natural reaction would be to do it, whilst you've got the engine in bits....but...my only experience with that is when I had 2 cracked retainers on my Vaux 2ltr "redtop" in my Westfield, some years ago...at the time, the internals were stocks, but even so, didnt want to just replace 2 of the 16 leaving 14 suspects (if a dodgy batch), so IIRC the head was whipped off (easy) and I fitted Ti replacements. Refitted cams, head, re timed, and I have to say it did feel a smidge different (stock internals but SBD taper throttle bodies, MBE management, 4-1 exh man, 209hp). Was then able to reuse them a couple of years later for the "special build" (272hp) that revs to 8750

So, if it were me, I'd go for it.