Stumped - How to Replace Tub Waste/Overflow w/ Very Tight Clearance to I-Joist
First off, thanks in advance for reading this. I have been lurking here reading all of the great advice and info for months before joining and posting this question.
As part of a current minor bathroom reno (mainly retiling floor/walls and changing out some fixtures) I am replacing a broken cable-actuated waste/overflow in a Jacuzzi tub while I have the walls open and can easily access the pipes through the subfloor. We're keeping the same tub, so all plumbing will pretty much remain where it is.
The only catch here is that the drain is a "direct drain" (not sure of correct terminology) and there is a very tight clearance for the overflow due to an I-Joist a few inches away. I would like to use a "clicker" drain here, ideally an OS&B clicker or something similar if possible as I have installed these in the past for our other lavs/tub drains and have been very pleased with them.
I have test fitted an OS&B ABS direct drain tee and it fits perfectly, but my problem is I cannot fit the ABS elbow and short pipe for the overflow to the tee due to this very tight clearance to the flange of an I-Joist directly in front of the waste pipe. I basically have 3" of clearance from the centre of the drain to the edge of the I-Joist flange. I have read that even slightly notching an I-Joist is a big no-no so that is out of the question here. Here is a pic (sorry for the quality) showing a measurement from the centre of the tub drain to the edge of the I-Joist flange (OS&B ABS direct drain tee is loosely screwed in here and measurement is from the centre of the drain):
One option I am considering is using an OS&B rough brass direct drain kit (314DQ-20CP) rather than ABS to see if this provides clearance for installation, however I'm waiting to hear back from their customer support on whether this will fit as they don't have a spec sheet for this kit posted online.
Are there any other options here that I am missing? The old waste/overflow extends further than 3" but uses a much smaller (looks like 1") flexible corrugated pipe for the overflow and so manages to barely clear the top of the joist flange. Here's a pic of the old one FWIW:
Thanks in advance for any assistance!