Hi I re-caulked my decks early this year, a couple of things I learnt 1. I bought Sika 290 dc out of UK for less than $30.00 a cartridge delivered. 2. The UK Sika was a different consistency than the locally bought stuff and easier to use. 3. Bond breaker tape makes it a lot easier to remove the old caulking, just cut down either side with a stanely knife and pull it out.
Also I used a small tenon saw with a couple of buttons fastened to the blade to lower the groove depth then a small chisel, then cleaned either side of the groove with sandpaper glued to a 5mm thick piece of wood. Did it