Recording a rock band in a small club

One of the bands I play drums in is calling it quits at the end of the year. The guitarist and vocalist have been playing together on and off for over 40 years, and have developed a good following. The vocalist is in his 70s, sounds stronger than most 20 year olds, but he's getting tired of the regular gig grind. In all this time, they've never released a studio record. The bassist and I have been unable to convince the other two to go into the studio to record some tracks for posterity. (Money is definitely part of their hesitation.) So, I'm hoping to record our last few shows and just maybe get something decent. We have two remaining monthly gigs at a local bar.

Any advice would be greatly appreciated.

The band: Vocalistelectric guitar through an ampelectric bass through an ampacoustic drumkit (just 1 rack tom, 1 ride cymbal, 2 crashes...)

The ONLY thing run through the PA is the one vocal mic. There's a (uncalibrated) decibel meter at the bar, and with the band playing it averages about 100 with peaks as high as 118 on some overzealous performances.

The Gear:

There's a house PA, but we're on our own running it. The board is a Yamaha MG166cx. The main outs run through an outboard eq. There may be a power conditioner in the rack. There are two FOH speakers on stands at the front of the stage, two Mackie Thumps for front wedges and a wedge next to the drum kit.

I've got a Tascam US-16X08, and a MacBook Pro running Cubase (need to brush up on my Cubase experience.) i dont have the greatest mics, but have been considering getting 1 or 2 slightly better used ones I've got:4 x SM57s2 x SM137s1 x SM581 x Beta52a1 x Beta56a1 x Beta58a1 x Audix D61 x AT20201 x MXL 9901 x MXL 991

The Room:

Dimensions are ballparked off the top of my head. 70 feet from the back of the stage to the opposite wall.35 feet wide.The stage is 1 foot high, 15 feet deep and 25-30 feet wide with a heavy curtain on one side and a solid wall on the other.There's a horseshoe bar sticking out 30 feet from the back wall, and a dance floor between the bar and the front of the stage.There's a 10 foot high drop ceiling above the bar/dance floor.

Initial Plans:Use the Beta52a and Beta56a for kick & snareIse the AT2020 for a drum overhead. Use a SM57 on the guitar amp. A direct out from the bass amp (if it exist) and/or the Audix D6 (or maybe swap for the Beta52a...?)Use a prefader aux send from the board for the vocal mic. (it would have any of the board's eq and compression. Not ideal.)Hang the 2 sm137s from the drop ceiling for room mics. I've got a few Shure A56D drum clamps which I believe I could clamp to the drip ceiling rails. Im thinking maybe 5 feet from the end of the bar towards the stage.

I was considering buying a budget multi-pattern LDC for doing mid-side with a figure 8, but I'm now thinking I might spend that money elsewhere.

I'm also considering (since we're only using the PA for the vocal mic) using my Mackie 1402 VLZ3 to run the PA, and tap the vocal with a direct out from the insert jack to the interface. I might be able to use the house eq with the 1402.

I'm purposefully not putting the interface between the vocal mic and the soundboard, as I don't want to risk latency )or other) issues.

So, waste of time and effort? Or possibly a great live record?