Ohhh... not very nice Dave
The good news is that the heel block looks like a nice easy job. Very clean break, and that dowel makes an ideal locating pin. Perfect candidate for simple wood glue.
The problems are in all the other things you need to check/fix/address before you get that far.
The first job on the list is to carefully examine that front cross brace and make sure that the glue joint is still sound across the full width of the body. And you also need to check that it is still properly seated in the kurfings around the sides of the body. I would also check all of the other braces and the reinforcement around the soundhole at the same time. The front will have flexed a long way before finally breaking and there is a real risk that this has broken the glue joints between the front and braces. If you do find any problems here, they need to be reglued first. It's a fiddly job, but it can be done through the soundhole and 'temporary access hole'. Normal white wood glue is the one to use, and you can use thin, flexible, plastic strips to work the glue between the brace and the front. I have taped 3cm strips of plastic to the end of wooden coffee stirrers to make tools to get glue into hard to reach places. The hardest part is clamping the braces if you have to reglue them. If there is just a small section near the soundhole it's easy, but if you have to glue near the ends of the braces it gets difficult. In the past I have had to make clamping cauls to put over the braces, wood blocks against the back of the guitar, and then used wooden wedges to press them apart to get the clamping pressure.
The next job is to reglue the bindings and purflings. This needs to be done before the neck is reattached to the body. The technique for glueing them is the same as I used on Project Uke, so check the pics there to see how I use sellotape to clamp them down. For the purflings you need to work some white glue into the breaks and it's OK to water it down a little (1/4 water, 3/4 glue) to help it flow into the breaks easier. But for the plastic bandings you need something that will glue them to the wood of the body and purflings, the first choice would be Weld-On Cement, then Duco, and last choice would be medium viscosity superglue (Green Zap is ideal for this). You will also need to replace the missing section of binding.
Once that's all done, you need to make a decision. It depends on how everything fits together, but the problem is that trying a test fitting can do more damage. You need to decide whether the fretboard will go back on the body as is, or whether you need to remove some or all of damaged front/rosette from the fretboard tongue and repair that damage first and then glue the neck. But that's rushing ahead and perhaps its best to wait until you've assessed the first stages.
Hope that's all helping Dave. And again, thanks for getting the pics up Greg.
When the going gets weird, the Weird turn Pro.