| Some of the 748's, mostly E models used the head designed for the S4 and ST4.
To fit those bikes the exhaust cam was lowered 20mm and uses a different cam belt to the "original" 748/916/996 types.
You can spot them by looking at the coveres than sit between the cams. The 916 will have 4 bolts holding it in place. The later type uses 5.
Check your 748 out and if theres 4 then you can use the 916, if there's 5 then you need to use the S4 ST4 type. | 
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