Well, it seems that I was right that you know next to nothing about nuclear technology.
First of all, you don't seem to understand the difference between tactical nukes and strategic nukes. Pakistan is nowhere near mastering miniaturization for its nuclear arsenal as far as information in the public domain is concerned and we are considering only information in the public domain that is verifiable because otherwise we may assume that Iran already has secretly produced tens of 30 kiloton nukes.
Secondly, IR-6 is not a dud nuke. It's a centrifuge.
Thirdly, the Little Boy was nowhere near a dud nuke. Nobody calls 15 kilotons dud. It is quite easy to implement. South Africa implemented it and used it for its arsenal. It didn't take the Americans much time to develop it in 1940s. There's nothing difficult to implement here. You split your fissile material into two parts that are kept apart until they are joined and create a super critical mass. The chance of predetonation exists but is in fact quite small. Iran is already producing metal uranium. And we already have enough uranium stockpiled for at least 2 - 3 gun-type bombs. Iran has been producing fuses for its missiles for decades. What part of it is difficult exactly?
Fourthly, you don't need to enrich it to 98%. Even 90% is enough for the core. The rest can be enriched up to even 60%. One more reason to see that you don't know what you are talking about.
Pakistan is also miniaturising strategic warheads
without losing explosive power.
Almost 40% reduction in warhead size.
Miniaturization of Pakistani nuclear weapons going on
at all levels. Previously it was thought the country is
deploying miniature tactical nuclear bombs but new
evidence suggests the country is also reducing the
physical size of strategic nuclear weapons.
Latest shaheen-3 has 40% smaller warhead
compared to shaheen-2.
Smaller size does not mean loss in power, it just
means the country can make sophisticated designs
which produce the same blast with smaller amount of
material. The miniaturising is possible due to more
complicated fission fusion fission design.
The reduction in the size of warheads also means less
drag while re-entry and higher speeds. Also smaller
warheads have smaller radar cross section and more
difficult to find and track for the enemy ABM.
An imminent side effect of miniaturising strategic
warheads is upcoming MIRV or MREV capability as
multiple warheads of Shaheen 3 size can be fitted on
large nose cone of Shaheen 2. Being a three stage
missile, Shaheen 3 currently cannot have MIRV /
MREV but saying that, all Shaheen series missiles are
Pakistan zindabad