PL1: thought it might be Contra as well, but unfortunately not

I'll have a look at the link that you sent - hopefully, it's comprehensive and this CAB I'm looking for is in fact there.
It is similar to Metal Slug in some ways, but not quite.....forgot to mention that in this particular game, the screen graphic shakes (I think) from to time when the a boss comes out, or an advancement to something more difficult.
Thanks
It's a side scrolling horizontal 1 or 2 player game that features a soldier shooting his enemies along a jungle brown terrain that with trees - the unique thing that I remember (I think) is that there's chunks of land (triangle shaped pieces of grass islands) that seem to drop from above and the soldier can jump on it.
I remember the cabinet graphics - shows the character in a muscle shirt and wearing sunglasses.
Sounds a bit like some parts of Contra, but the sideart characters have headbands instead of sunglasses. 
Maybe try looking through the cabs in your Front End cabinet directory or here.
https://www.arcadeartwork.org/index.php?/category/19
Scott