The Diamante is 10:1 CR. To me, that says interference potential. This is from an on-line reference:

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*10:1 compression built motorÆs are interference meaning valves and pistons will collide if the timing belt snaps.


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However versions of the SOHC motor with 10:1 compression pistons are interference.


EEK6g72 pages

The Gates catalog says it's not an interference engine:

Gates Catalog

Frank

'89 [color:"white"]G-Raider[color:"white"] [color:"black"]Supercharged 3.0L, MegaSquirt 2, lockup A/T, 2.5" exhaust, 172k, Cibie H4s/Oscar SCs, Hella Micro DE fogs, Cobra CB, Superwinch hubs, LSD rear/Aussie Locker front, Bilsteins, Lifeline AGM, Rust-Oleum