There seems to be a shimmy at about 63-70mph ... any one have issues with this?

There's also a thump sometimes (often times) when the breaks are applied.

Any help with these would be great.

 

Have the tire balance checked, if there off balance it will cause that shimmy at speed. Also check your air pressure.

 

Thunk when brakes are applied could be your strut rod bushing pockets in K frame. Ive seen these come loose and cause this noise upon brake application. If it is a repetitive thumping then you probably have warped brake rotors. Your shmmy could be tire balance, but if the steering wheel shakes ide to side during this it is probably a tire problem, rotate may fix this.if not to bad.