I consider some of those 1600s to have had a lot of material cut out of them to fit intercoolers, rather than 'minimal'.
You can just tell that the front panel that goes behind the bumper has been trimmed from the inside or removed altogether. I've even seen 1600s with the back of the bumper chopped out!
Many with huge intercoolers also have the rod that goes from the top of the radiator support down to the front of the chassis removed altogether - this makes the top of the radiator support panel flex heaps! This section holds the bonnet down too!
Zachary
I know you are not talking about chris's, jeff's or mine (pics at the top) as we cut 'minimum' amounts from the front to fit the cooler. I have retained a 'fabricated' rad support car and chris has the factory one.
Believe me I have procrastinated over this for a long time. Unless you have a magically thin radiator between your headlights you cannot run anything much smaller.
I know of some cars which cut everything out of the front to fit an i/c. None of us have done this and it should be quite clear from the pics. About 2cm either side and a scallop at the bottom where a big hole exists anyway.
sorry vaughan cannot help with the fj dimlema. Did not know thr fj took up more room. Maybe try maddat who uses mick's metal craft for i/cs and rads.