what's the difference between the convertible and hardtop add-on gauge pods???????

i know a buy who has a used add-on style dual gauge pod for sale. only wants $10 for it. the problem is, its for a convertible. i got a hardtop. will it fit mine? i plan on molding it to the stock a-pillar so it would be permanetly attached. so a little work would be all right.

if anybody knows, please let me know.

thanks