2)
Is 1) a Blakely rifle? the muzzle swell is confusing me

And this is what they were converted from.....
Allen, From the Blakely site for which you posted a link comes this which explains exactly what Blakely's agents did to get those 68 pounders from Low Moor converted and sent to the Confederacy as conversion rifles.
Low Moor guns seem to have been used primarily in the Western Confederacy, imported through Mobile, Alabama in one shipment.
8 inch Blakely Low Moor Gun
The 8 inch Low Moor Guns 1862
In addition to the relatively well-known 7 ˝ inch conversions the Low Moor Company also adapted the cast-iron tubes of the Royal Navy 68 pounder gun into a much more effective 8 inch calibre rifled piece. This was originally a smooth-bore shell-firing gun, the Navy’s largest piece before rifling was introduced, and weighed 10,500 pounds. As with the 7˝ inch conversions the 8 inch barrels were either made new or from commercial stock; the work done either by Low Moor or by Low Moor and Fawcett Preston. Blakely had first demonstrated this inexpensive adaptation in 1857.
The conversion process was different from the 7˝ inch guns. The cast-iron tubes, with all their traditional “ornamental” rings and modelling, had the breech end turned into a cylinder, and, instead of the breech band, a long,
well-rounded steel jacket was forced on to just before the trunnions;
the muzzles keeping their traditional moulding. The rifling was also different from the 7˝ inch guns; just three “centrical” right-hand twist grooves were cut. This all allowed an increase in the maximum projectile weight from a 68 pound round-shot to a 130 pound Scott-pattern flanged bolt.
There were, it seems, just six of these large 8 inch rifled guns, imported into the Confederate States. Three were brought in through Wilmington during the spring of 1863, to supplement three already present. One of these was retained at Fort Fisher, Wilmington, one was installed at Battery Wagner near Charleston and one at Fort Morgan, near Mobile.
Allen, the close up of the Fort Morgan cannon shows this well-rounded steel jacket quite well. Mike and I studied this very Fort Morgan, Blakely conversion rifle at West Point, New York and it is in remarkable condition, except for a missing trunnion. The 3-groove rifling is very deep at .400" and the appearance is striking with those 3 huge grooves. The Blakely or Low Moor foundrymen must have polished the whole gun to the equivalent of 600 grit. The surface shines, even to this day, and a fine patina has prevented any red rust from forming.
Tracy and Mike