The main reason for trimming to length is for location of the neck turning mandrel which buts up against the case mouth to determinethe length of cut.
I neck turn because i use neck-bushing dies which will only size correctly and hold the same neck tension if the necks are all the thickness.
If you want to go that way, in view of what the other guys have said, you will need a primer pocket uniformer and a flash-hole de-burrer, i uniform the flash-holes with a normal drill bit.
I use K&M services, products. i dont think they have a website but Sinclair international carry everything you need
As Jimm says lapua do not make 25-06 brass, my buddy Brit forms his from Lapua 30-06 brass with excellent results.
With carefull adjusting of your die you can neck down to create a shoulder which is the exact length for your chamber, but an intermediate sizing to 270 would be reccomended first.