The old method used to be to use conduit round-elbows and rount-T
boxes.
I suspect that is because they allow the use of gaskets & brass M4
screws, so providing better water proofing than the mere "snap
together elbow".

A garage has quite a temperature range, so watch the expansion re
plastic.

Saddle clips require precision location, snap-over single clips have a
slot so tolerant of miss-location.

As mentioned MK Egatube fittings (including bush-female adapter) are
the nicest, keep their finish well and generally fit together. There
are some tubes which are slightly oversize and fit far too tightly (or
not at all) into fittings, avoid.