I just put a Brit rad (3 core) in Ha-Ha. 2 core one has same fitting problem.
The screws in these rads are now 6mm x 10 long, instead of the little hex head self tappers.
I used a small round file to open out the holes in the cowl, and trial fitted them all on the bench before fitting to car. Make sure all 6 bolts screw in by hand, with both cowls on rad...
Also, I slotted the centre rear bolt hole (in the upper cowl), so i can fit the screw into the bottom cowl before it goes into car. Then fit the upper cowl and slide down over the bolt.
WARNING: If radiator comes without these 6mm bolts (as mine did) make sure the ones you buy are no longer than 10mm or they will punch holes in your shiny new rad core..
Eh Gafmo, J_A_M, et al...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
