Replacement opener motors with large beam in the way

Hello,
I've got a situation where I need to replace the opener motors but there is a large beam (18" x 8" or so) running around 8' from the doors and parallel to them.  Basically the original home owner cut fairly large holes in the beam to allow the openers to go through.  So I'm looking for recommendations on what kind of openers to get.  I'm thinking that a screw drive option is the best way to go to fit through the holes in the beam.  One of the existing openers is a really old Genie 450 model (Screw drive).  Also, what is the best opener to get when the carriage movement could be limited by having to partially go through the holes in the beam?

Thanks for any help / advice!

Screw drive openers generally take more headroom than a standard belt or chain opener. I would suggest a Marantec garage door opener. The rails only take about an 1" of room and the trolley moves along inside the rail. Also the powerhead on the newer Synergy series of operators can be mounted normally or sideways if backroom is an issue.

Thanks for the suggestion Brian.  Do you know how wide/high the tracks are for the Marantec openers?  Basically they need to fit through the holes in these beams and the holes are around 4" in diameter.  Thanks.

Offhand I don't but the trolley is around 2-1/2" wide so the rail is probably around 3" wide. You could contact Marantec or your local Marantec dealer and they should be able to get you the exact measurements.