Hard top fit problems

[MX51ROD]

Just picked up an Ebay purchase of a MX5 hardtop , taken from a 2004 Mk2.5 and fitted to a 2002 Mk2.5
Having a fit problem , when clamped down on the head rail the hardtop seems to bow up slightly in the centre so not forming a good tight seal , and as a result wind whistle
Before I start shifting clamps etc any tips ?

[MX-5 Lazza]

Is it attaching to the Frankenstein bolts at the rear and the side clamps properly?

[MX51ROD]

Yes all clamps have engaged correctly and the the H/T is secure on bolts at back , one thing that may have a bearing ,is the head rail seal/rubber is compressed to shape of the soft top , and as the car is over 10 years old it may not be springing back to its full shape , a temp flexible foam seal has been stuck to the underside of the front lip of the hardtop and this has formed a good seal ,and wind whistle has gone

[MX-5 Lazza]

Could it be clamping down too tight at the front?

[MX51ROD]

That may be the problem , the H/t bows up a fraction in the centre , but I did not want to start adjusting without advice . nice day time to start fiddling

[MX-5 Lazza]

I don't have a hard top so have no 1st hand experience but I know the clamps should be no tighter than they are on the soft top (which shouldn't really be all that tight).