| I also have a complete 748sps gearbox that would go straight in (£65 plus p&p to you) but beware.......
The later boxes had a longer output shaft, I forgot this on the "putting a 996 engine in your 888" post.
IMO, put the ST4s engine in. If you strip your 888 to get the engine out your half way there, and if you have to pay someone to strip and rebuild your 888, you probably pay for the ST4s engine too.
My std st4s engine, plus a cam dial in and a decent exhaust, was set up to produve 117 at the rear tyre. | 
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