Been a while but I finally made some progress on my
BX25 Valve Project. Ordered and received the detent kit, additional fittings and hoses to hook up my old hydraulic top link and to run the BH off of the new valve. The detent kit was not quite what I thought it would be but should work fine for running anything that needs continuous flow. I had thought it would just add a detent to the existing spring-to-neutral spool, but it ends up removing the spring so you can only lock the lever in either direction. So, it really can't be used for running a double acting cylinder as is. But I do have the old parts to convert it back if I need to. Should take about 5 minutes to change it out.
I did make one mental screw-up (so far :laughing

and ordered one too many male QC's and one too few female QC's so I couldn't make the last connection to try running the BH off of the detent valve spool. I think you can see in one of the pic's the two unconnected lines (near each other). I will pick up the missing QC locally this weekend, hopefully.
I did check out the valve as it is now (i.e., BH not hooked up) to check for leaks, etc. I started the tractor and first listened for any loading of the engine with the valve in neutral in case I somehow deadheaded the pressure, but it ran fine at idle. Added some RPM (about 1700-1800), and tried operating the FEL. After a short pause to purge the air I assume, the FEL seemed to work fine, though I didn't do anything to cause the pressure to max out. It did seem to run a little slower than before the valve was spliced in, which would not make much sense if the FEL valve is the first in series, so it could just be my imagination.
As you can see in the third photo, I hooked up my old hydraulic top link to trial it and it worked fine, though noticeably slower in the extend vs retract direction. The valve is rated for 8 GPM, which is about twice what the BX pump delivers to hydraulic attachments, but maybe all the QC's have some impact on the speed?? At some point I will time the FEL up and down with the valve in and out of the system to see if speed is impacted. If it is, that won't be ideal for running the BH off the valve.
For anyone interested, I have about $400 invested in this set up so far with the valve (+ detent kit) not quite half of the cost. The steel for the mount was scrap I had, and I was able to reuse the old top link hoses and male QC's. The grapple thumb should be about another $400 when I add that next year (assuming prices don't jump much). Everything is hooked up with QC's and the valve is mounted with wing nuts on the bracket, so I can put everything back to OEM whenever I need to.
Once I finalize all the hook ups and test out the BH operation via the valve, I will organize the hoses a little better and get some hose protection fabric. So, more to come in a few days, hopefully. Looking forward to adding the grapple thumb by this time next year. :thumbsup: