Using a calculator on a website I cut each wire leg to 2.857 m and stuck up the dipole in the driveway.
Set up the FT817 on a camping table nearby, along with the battery and MFJ Tuner/SWR meter
The SWR was not too bad, about 1.8:1 across the whole 12m band. Getting the full 5 w out.
I then took the squid pole down, added the 40 m dipole in underneath and hoisted it back up.
The SWR came down to pretty much 1:1 across the whole band :)
The SWR on 40m looked good too, so the 2 dipoles seem to get on well...Tried a few calls but no reply, the 12 m band seems rather underutilized...I had a tune around and heard a couple of weak JA Japanese signals, I tried calling one JA but no luck with my QRP signal. Hopefully works better out in the field...