Ok, not Locost, but my tintop...the plug holes are waaay down in the head so how do I do a compression check? Got a gauge and a flexi extender, but I can't get enough torque on the extender to get a seal on the plug seat.
Do I need a solid extender, or am I missing a trick here?

Yes but beware most some tool manufacturers charge way over the top for these, I bought 2 sets very cheaply to make up a cylinder leakdown tester. The supplier was chrometrader0 on ebay
see http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130244440117

Old stock items and the threads were damaged on one adaptors I was damage but that was easily fixed.
Rescued attachment plug5.JPG

Thanks BT, just bought some of those, £3.50 inc post