Fitting aluminium S3 fuel tank in a short cockpit live axle car

[Gridgway]

In my 1980s live axle car that I am restoring, I have dispensed with the old steel tank (being extremely rusty inside) and got the carb S3 aluminium tank complete with "fuel tank strap with bolts" on the caterham parts website here.  This was as advised by Caterham parts.  I have got 4 tabs on the chassis at  the bottom corners of the tank.  If I put the strap across the front of the tank and the bolts in the front tabs, it just pulls the strap off the front of the tank.  The bolts don't seem long enough to reach the rearmost tabs.

The old tank had the straps around the tank in a longitudinal direction.  My 90s long cockpit live axle car has the same arrangement of longitudinal straps but with the ally tank.  They have to be longer as the outside dimensions of the ally tank are greater.

Does anyone have this locating arrangement to advise on fitment please?  There's nothing in the assembly manual as the tank is pre-fitted in the CKD.

Thanks!