jcalg1 - MASM and Gas Attack

Naïvely I assumed that assembler was assembler - this assumption like the best assumptions was based on ignorance. I have done assembler back in college days college on old PDP-11, later in 6502 and a little 68000 from this it never occurred that different assemblers (with the same target language) could be so very different. As jcag1 compiles under MASM - and XCode is Gas (gcc) they are quite different. My attempts to Google-up a gas version of jcalg1 did not yield.

The options from here seem to be:

1. Convert jcag1 to Gas. I have found a tool that claims to be able to do this intel2gas - but there is a large amount that it just can't handle.
2. Use the .intel_syntax directive in Gas and fix up all the errors manually. This directive makes gas use the AT&T syntax which is closer to MASM.
3. Modify my approach - change the original windows version of Cello so that it saves and opens files that are not compressed and thereby just side-step this problem. This would allow me to still create sample files.

Of these approaches the last will obviously work - however I will have a crack at the .intel_syntax directive and see if it has millage.